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AT27C040
0189F–EPROM–4/03
Atmel’s scaled CMOS technology provides low active power consumption, and fast program-
ming. Power consumption is typically 8 mA in active mode and less than 10 µA in standby
mode.
The AT27C040 is available in a choice of industry standard JEDEC-approved one-time pro-
grammable (OTP) plastic PDIP, PLCC and TSOP packages. The device features two-line
control (CE
, OE) to eliminate bus contention in high-speed systems.
Atmel’s AT27C040 has additional features to ensure high quality and efficient production use.
The Rapid Programming Algorithm reduces the time required to program the part and guaran-
tees reliable programming. Programming time is typically only 100 µs/byte. The Integrated
Product Identification Code electronically identifies the device and manufacturer. This feature
is used by industry standard programming equipment to select the proper programming algo-
rithms and voltages.
Switching
Considerations
Switching between active and standby conditions via the Chip Enable pin may produce tran-
sient voltage excursions. Unless accommodated by the system design, these transients may
exceed datasheet limits, resulting in device non-conformance. At a minimum, a 0.1 µF high
frequency, low inherent inductance, ceramic capacitor should be utilized for each device. This
capacitor should be connected between the V
CC
and Ground terminals of the device, as close
to the device as possible. Additionally, to stabilize the supply voltage level on printed circuit
boards with large EPROM arrays, a 4.7 µF bulk electrolytic capacitor should be utilized, again
connected between the V
CC
and Ground terminals. This capacitor should be positioned as
close as possible to the point where the power supply is connected to the array.
Block Diagram
